Fox Foxbody dies at idle and when reving fast

1991 Foxbody
replaced : Fuel pump , radiator , distributor , coil , starter coil,

When I changed radiator my fuel pump stopped working replaced it with temporary fuel pump drove it for few days one day when coming home from work with low fuel , forced the fuel pump alot and fried it since it wasnt high pressure i orderd new 255 lpm fuel pump now my car idles for few seconds then dies and when i try to rev it , it just dies
If i leave it revving it'll stay alive im able to slowly rev all the way to 4k rpm but as soon as i quickly try to rev it seems like the fuel cuts off but if i unrev the car a little it'll come back to live.
 
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Pull the codes. It could be a few things.....catalytic converters, timing, pip, maf,....a bunch of stuff.
 
catalytic converters are modified to say they are fine

That’s not a thing on the Foxbody. It doesn’t monitor cat efficiency as there there is only a single pair of o2 sensors and they are there just to adjust A/F. That jazz all came with the 4.6L engine in 1996 with 2 pairs of o2 sensors


Do you have an SElf test port near the wiper? Jump the small test plug to pin 2 on the larger one. Disregard wire colors. This is pin 46 to pin 48. Your cel should blink the codes.

Dotted red is the jumper.
67D67950-A06D-4340-A6B4-B9A17B8AAD32.gif




What’s the full list of modifications to this vehicle? What sort of electrical/ECU mods were done?
 
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One of the most missed things back in the early 2000s was clogged catalytic converters.

If you are using the factory ecu and harness, you can ull the codes. There are so many variables that will make a car run bad. Without codes you need a thorough knowledge for diagnostic processes or you can spend a lot of money for nothing.
 
That’s not a thing on the Foxbody. It doesn’t monitor cat efficiency as there there is only a single pair of o2 sensors and they are there just to adjust A/F. That jazz all came with the 4.6L engine in 1996 with 2 pairs of o2 sensors


Do you have an SElf test port near the wiper? Jump the small test plug to pin 2 on the larger one. Disregard wire colors. This is pin 46 to pin 48. Your cel should blink the codes.

Dotted red is the jumper.
67D67950-A06D-4340-A6B4-B9A17B8AAD32.gif




What’s the full list of modifications to this vehicle? What sort of electrical/ECU mods were done?
My bad i meant as my catalytic converters got hollowed thats so theres nothing inside my catalytic converters theres was once a time something got loose inside and asked my father/previous owner and said that they got hollowed out